will the increasing CH2 in a carbonyl chain increases the reactivity or the other way around?

Question

lets say C2H5OH and C3H7OH. how bout phenolic compunds? the same?

thanks alot!

sorry! it's carbon chain.

Answer 1

What you're describing are alcohols, not carbonyls (which have the C=O group present). Alcohols usually react via the protonation of the hydroxy hydrogen, and this decreases as the alkyl chain gets longer. Phenols are a completely different story, as the delocalization of the benzene ring inceases the acidity.

Answer 2

First, let's be sure you mean what you say... "Carbonyl" refers to the C=O group. I think you just mean the carbon chain, since you turn around and refer to alcohols, which have no carbonyl.

That having been said, carbon chain length's relationship to reactivity depends on the functional group at the "business end" of the molecule. It also depends on whether that chain stays a single, straight chain or is allowed to branch. (Ask anyone who's studied substitution about that...)

I'd say narrow your interest to a particular class of compounds (alcohols? aldehydes, etc.) and specify the chain as straight or branched, then re-ask your question.